Telegraph apparatus



March 13, 1945.

F. wARBuRToN 2,371,367 TELEGRAPH APPARATUS Filed Aug. 18, 1944 6 Sheets-Sheet l Inventor -Fred Warburfon y flaw aim/M1 Attorney N. r W

F. WARBURTON 2,371,367

TELEGRAPH APPARATUS March 13, 1945;

6 Sheets-Sheet 2 Filed Aug. "18, 1944 Invenlor fled Warburfan March 13, 1945. F. WARBURTON TELEGRAPH APPARATUS Filed Aug. 18,1944 6 Sheets-Sheet 3 Inventor Fred Warburfon Attorney March 13, 1945. F. WARBURTON TELEGRAPH APPARATUS e Sheets-Sheet 4 1 Filed Aug. 18, 1944 d u arburfon By Mllorr xey Filed Aug. 18, 1944 6 Sheets-Sheet 5 FIGS.

lnvenlor Fr'ez/ Warbur'fon March 13, 1945. WARB T N 2,371,367'

. TELEGRAPH APPARATUS Filed Aug 18, 1944 6 Sheets-Sheet 6 63 nvenlo: Fred Warbwfon Attorney 'bers of "elements; for

' the preparation Patented Mar. 13, 1945 L w-rec.ems-s mam? TELEGRAPH A PARATUS Fred Warhol-ton; London,

Cable and Wireless Limited, London, England, a

- British company I England; assignor to 'Application AuguStlS,1944;"SerialNo. 550,QiS6 I In Great Britain September 16,1943 I I t l r t This invention releates to telegraph ting apparatus actuated under the, control of 1 5f record strip, such as aprforated tape, ,bearing a i series of words represented inacode comprising permutations of elements such as'dotsand dashes. A code of this kind may bebeseec the Well lgnown Morse code and consist, for example, of

the code known in telegraphy as the Morse Wheatstone code or double current'cable code. In such a codethe various letters, digits, or other symbols transmitted are represented respectively by code permutations containing difi'erent'numin Morse code the letter'E isfi'epresentedbya singledot and the letter T by a single dash while the less common letters are represented by four elements. Although the invention is"particularly applicable to the transmission of such codes, it

exampleas; is well known,

may also be applied to the kind of code thatis I used'in private teleprinters and'in which each letter or the like is represented by a fixed number (such as five) of code elements.

j Although the invention may be applied ease transmission, it is mainly concernedwith thejcase' where the transmission takes placeby wireless."

"lhe'n, as is well known,,the atmospheric conditions vary from time to time and the signalre: ception often deteriorates so that it becomes advantageous to repeat each word, the transmislsion .of each word in a series ofwords .being "re peated before the transmission of the next word. This involves a substantial increase in the time ting apparatus, actuated under the control of a I graph transmitting" therewith will now'b'e 26 claims. :'(,Cl.- 178-47) mechanism, may, cause each section of the strip that contains a record of a word to undergo two separate anddistinct feeding movements which take place insuccess ion'and"during each ofwhich the code representations aref' 'e'iiplored for" the transmission of the word; 1 Thus, when thecode perforations for the wordcover more "than-apre determined length of strip, the iatter m y be caused togather betweentwo pointsat which'the code representations are explored respectively during the two feeding movements. '-'Generally, the code representations will be in' the'for'r'n 'o'i? perforations punchedin paper tape; the per-fora tions being exploredby peclirsboth-forthe initlali transmission and for the repeat transmission; Accordingly; there may be"tW', r pairs or peckers;

one for'the initial transmission of each word and theothe'r for the repeat transmission, thepa'irs of peckers'being alternately brought into operation for a period corresponding to the length-ofthe word, and the alternate actuation of the-pairs of peckers corresponding to the two feeding movements of the tape-providedffor theinitial and repeattransmission of'the word i J j Th'e' physical characteristic of the record which indicates-the division between, two words may consist of the-usual gap provided between :the last perforationin one word and'th'e first perforation int'h'e next word. 'Then the apparatus -is arranged so that, on detecting'this gap, the repeat transmission is initiated and continues'until the tape is' once more drawn tautbetween the two aforesaid. points at which the code perforations are explored respectively during the two feeding movements,fwhereupon the apparatus is auto matically rendered capable of detecting the" beginning-of the next word and'eflectin'g theinitial transmission thereof. 7 V In order that-the invention may be clearly understood and readily carriedinto effect, telepie. with reference to the accompanying draw some parts being omitted to avoid too 'greaticomf record strip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes, is furnished with mechanism for detecting the division between two consecutive words and with transmitting mechanism responsive to the detecting mechanism for repeating the transmission of each word before the transmission of the next word. The detecting ings,in= which:; I F u e 1 i a Pe spe ti I e iof the app ratu plexity and consequent obscurity; fi r 2 appearing in Figure 1 and associated parts that is a perspective-viewof certain parts ar omitted from Figure 1, 1 t

Figures 3., 4 and 5 are further perspective views oflportions of the apparatus appearing in Fig- Figures 5' as 7 are diagrammatic side eiev'ations' of an assembly in the apparatus; the assemapparatus in" accordance described, by way off exam spring 11.

a framework which for the sake of clarity has been omitted except such few-r portions" of. the" framework as have a= special functional relationship with the apparatus.

As is usual, the apparatus is operated by paper.

tape |.(Figure 1) previously formedv with code. perforations representing the signals to be transmitted. As shown in Figures hand l8} thBrt8.-D ;1S

also formed with a centralzline'of. centerholesZe which enable the tape to be fed through the apparatus by sprockets 3 and.-4-each.- provided. with ten equidistantly spaced teethtd SQ-xthfit.

one revolution of a sprocket the tape is fed forward an amount equal to the distance between ten :centerholes. .2 andsinlone .tenthof a sprocket. revolutionthe tapedscfed forward thedist'ance. between gtW-= consecutive centerlioles which may. be. referredto asone .centerliolefeed'.

When eachiwordlin a-signal. is-. ,t0. be transmitted.on1y once.the sprocketwheels 3and.4=are r0.- tated. clockwise; simultaneously; and the: tape. is explored or sensedbyrpeckers fl'andfl (Figures 1, 4 2 and i which. are-raised, at predetermined. in: stantss to determinethepresence :or. absence: of. code perforations.- along the. tape I.. On the. other hand;.when each word.- is.,to be transmitted. twice,- the. sprocket. A. is stationary during. the first transmission while; the sprocket. 3. feeds. the tape-past the peckersjand I and the tape-gatherss betweentthe: sprockets. 3 and. 4 ass shown in Figure-1; For the repeatvtransmission. the

sprocket 4 feeds the. tape. while. the. sprocket 3 remains stationary-.1 During this repeat trans, missiom. the'packers. 6. and .1 are: disabled and two further. peckersBUandS; which have previouslgbeeminactive; become: operatives Therefore, in as words.' twice .transmission. each. word is first transmitted under. the controli of; the. sprocket 3i and the peckers. S and 1; and thernbefore any further; WOIdriS transmitteduit is. transmitted again: undentheecontrotoi the; sprocket it and the: pecker-s. 8: and: 9}. The; some electrical: con. tact mechanisnn is. used. for both. transmissions as-w-ill beidescribedpresently;

--Th'e':tape- I: passes over a. platform (notshown) which: holdsthe tape engagement. with. the sprockets-sand! but which is shaped so -as to enable the: sprocket-teeth; 5a; and the four. peckers 6;];3 and= S to.cooperateawithmhe tape; The platform. also permits two center peckers I 0x and {in (Figure '5) 3 to.- determine whether: or-not there is a loop of tape, such as thatshowndn-Figurel, gatheredbetweemthe: sprockets 3sancl 4 The latter are respectively fixemto shaftslz and 13 (Figure 1 journalled-im a paper presser mam.- ber; i4=pivoted at lite-theefmme.andmaintained. im contact-with. a.- stop. 1.8% by; a. spring. ll When it is desired 'to release the paper: tape; the sprockets.- are: lifted. away from. the platform by turningthe member. t4 against theactionoi'. the

So-"longas th apparatus. is in operation, a shaft 1 8 is constantly rotated. inthe. directionlof the arrow [9 (Figure 1=) and-this shaft carries four eccentrics 20,21, 22 and23which drivethe various. portions. of the. a.pparatus.-. The; eccentrio's 22 and 23 are arranged; in the way debelowto. drive; the. sprockets 3.-andl- 4 in almanner. such that,. When;- the tape. is. fed}..a.

- of peckers 6, l and 8, 9.

one centerhole feed takes place during the time occupied by one revolution of the shaft l8. Therefore, all the parts driven by the shaft l8 operate in phase with the feeding of the tape or, conversely, the feeding of the tape is timed in accordance with the actuation of such parts. These parts include a rocker 30 (Figures 1 and 5), for actuating thetransmitter; contacts and peckers'i', I, 8 and 9,' which is rocked continuously about a spindle 3! (Figure 5) by the eccentric (Figure 1) acting on an eccentric strap 24 having an arm 25 pivoted at 26 to one end of ar'lever '2'! (Figures 1 and 5) centrally pivoted on a. fixed spindle 28-- and formed at its other end with:a. forkrZE-engaging a pin 32 on the rocker 30. The eccentric-2l rocks a frame 33 (Figures 1 and .2) about a. fixed spindle 34 and this frame seryesito operate mechanism for controlling the selection'of the sprockets 3 and 4'a'nd the pairs The eccentric 2| is connected to therocking frame 3.3 through an eccentricstrapii'fi having an arm 36 pivoted at 31 teen" extension 42 of the frame 33;

, The sprocket 31s driven through the medium of'a pair ofratchets 38 and 39. (Figure 1) fixed to the shaft I2 and the sprocket 4' is driven by a pair of ratchets 60 and 6! (Figure l) fixed to the shaft; 13. The ratchets 38 and 39 are rotated by pawls 40' and 41. The pawl 40 is pivoted at 43 to an arm 41 extending from a strap or on the eccentric 232' This pivotalconnectionis suspended by. a link. M pivoted on a fixed spindle"45.r Similarly the pawl 4.! is secured by an independent pivotal connection to an arm 49, on astrap mounted on.. the eccentric 22, and to a second link 46 hanging from the spindle 45; The .ratchets 60 and 61 are actuated respectively by pawls 5'0 and 5! pivoted respectively. to links 52 and 53hangingzfrom a fixed spindle 54. The pawls" 507and5l vlie outside the pawls. 40 and, the ratchets 60 and 6'! being spaced apart further than the ratchets. 3a and 39; The pivotal connections at the lower ends of the links and 52" are connectedby a link 55' while thoseat the lower ends .ofthe links 46 and 53 are connected by a link 56.1 Accordingly the pawls 40 and 50 are" moved' to-and-fro simultaneously by the ec-.- centric 23 andthe. pawls 41 and; 5| are moved to-and-fro simultaneously by the eccentric 22'. The eccentrics 22 and 23 are mounted. 180 out of 'phasewith each other so that the. pawls4l'l and. 5 0are. advanced whilethe pawls 4i and St are being withdrawn and vice versa..

Each of the ratchets. 38; 3.9', and Bihas-.ten teeth ije. as many teeth as there are teeth. 5 on .the sprocket. 3j0r sprocket l, and. the ratchets in each pair 38,39 or. 60, 6| are set so that each tooth in one ratchet lies mid-way between adjacent teeth onthe other ratchet. This appears in.Figures 6 and '7 'whichshow the manner in which the ratchets 38. and 39 are mounted on the. shaft 12'. The. arrangement is,such,.,thereiore,,that .each' centerhole .feedtakes place in two steps,1.in thefir'stpf. which the pawl 4] acts; on a tooth on the ratchet 38. toturnthe. sprocket '3 through one. twentiethof a revolution andin the second step the pawli40. acts on the ratchet 38 to turn the. sprocket 3. through. a further twentieth of a revolution. Thus, referring to Figure 6', at, the end. of the first step the. pawlv 4| reaches the position shown, having advanced. the. ratchet tooth. 39a to the position.- shown while the pawl 40 is withdrawntothe position. shown. Then, for the second. step,,the.l-pawl.40. is v ad:- vanced while the. pawl 4| isv withdrawn and, in

advancing, the pawl 40 engages and feeds for-z ward the ratchet tooth 38a; Now, it is to be noted that it is the .movement of the ratchet tooth 3911. that causes the tooth 38a to be brought to a; position in whichvitcan be acted on bythe pawl 40, 'Accordingly, from engaging the tooth 39a neither of the steps in a centerhole feed will take place and the sprocket 3 will be disabled. Therefore, whenever the sprocket 3 is to stop. feeding, the pawl 4|, in its forward movement, is prevented from engagingthe ratchet 39 by a stop 62,'on a discrimiswung'downwards away from a fixed stop 51, which appears in Figures 6 and 7 butis omitted frond Figure 1, against the action of. a wire spring 65"which acts against the tail 64, isbent round a fixed rod 66, and reacts against a fixed rod 61. A similar spring 68 acts on a short tail 69 on the pawl 40, this spring also being bent round the rod 66 and reacting against the rod 61.

- The ratchets 60 and 6| (Figure 1) are operated and controlled in precisely the same way as the ratchets 38 and 39. Thus, the pawl 51 has a tall 10 and, when it is-necessary to disable the feed sprocket 4, a stop 12 on the discriminatin 'mem ber' 63 is raised in front of the tail 10 so that, in theforward movement of the pawl the latter is swung downwards and misses the ratchet Bl.

Wire springs 13 and 74, which react against a fixed rod 15 and are wound round a fixed rod 16, tend to maintain the pawls 5B and 51 in their raised positions, the spring '13 acting on the tail and the spring 74 on a shorter tail II on the pawl 50. Return movement'of the ratchets-is prevented by resilient detents-(not shown in Figure 1) such as the detent 1! appearing in Figures 6 and '7. Locking stops l8 and 19 act on the pawls tolock the ratchets at the end of each operative. pawl stroke and prevent the ratchets from continuing in their rotation. This is effected by the wedge action of the locking stopson inclined surfaces 80 (Figures .6 and 7) on the pawls. 1

Before proceeding to describe the manner in which the apparatus functions as tape passes the peckers, the nature of the code used in the present example will now be outlined. Thisis the'well known Morse Wheatstone code in which a dot-is represented during one centerhole feed or period, i. e. the time taken for the shaft l8 to make one revolution, by a mark condition occupying the first half of the period and'a space condition the second half of the period. A dash occupies two whole centerhole periods and comprises a mark condition occupying the whole of the first period and the first half of the second period and a space condition occupying the second half of the econd period. Thus, both a dot and a dash start with a, mark condition and end with a spacecondition. The mark and space conditions may be represented in the transmission line in any convenient way. For example, amark condition may be rep,...

resented by connecting the line to a source of current for the required period and a space condition by disconnecting the source from line .or reversing the current for the required period. In

the arrangement shown inFi-gure 1 a'mark condit'ion is set up by closing contacts Bl toconnect the if the pawl M is prevented downwards (as shown in Figure?) away from' negative side of the source 82 to the lineL and a spacecondition iseifected .by closing contacts 83 to connect the positive side to the lineL.

In the tape, a perforation, such as the perforations 84, 85, 86 and 81 (Figure 8) is located above the 'row of centerholes 2, as viewed in Figure 8, for each change over from a space condition to a mark condition. These perforations are explored by the pecker 6 (Figures 1, 4 and 5), when the peckers 6 and 1- are in -action,.or by the pecker 8, when the peckers 8 and9 are in action. Thus the 'peckers' 6 and'.8 may be referred to asmark peckers. On the other hand, for each change-over from a mark condition to a spaced condition, a perforation, such as the perforations 88, 89, 90 and 9|, is provided below the row of centerholes 2.. .Such perforations are explored by the pecker-.1 or the: pecker 9, whichever happens to be in actionatthe time, and these peckers may be referred to. as th peckers.

Now the perforations Hand 88, which are in transverse alignment'with a common'centerhole,

represent a dot and areboth effectivein a single centerhole feed. The perforations 8B and 90, on

the other hand, represent a dash, and are respectively in transverse alignmenttwith' consecutive centerholes to be effective in consecutive centerhole feeds.

To explain'preciselythe effect of these perfora tions in relation to the peckers, let the peckers 6 and 1 be considered to'be in action and, incidentally..it will be noted particularly from Figure 4 that" the mark pecker 6 is heldxbya spring 92 against an edge. 93.0n a fixed stop 94'while a spring 95 holds the space pecker 1 againstaned-ge 96 which is slightlyin advance of the the; pecker l is at all times slightly ahead of the pecker fi with respect to the direction in which the tape] is fed. When the 'dot perforations 84,18 (Figure 8) reach the "pecke'rs 6 and Lprior to the first step in a centerhole feed, during the completion of the previous centerhole feed by the'pawl 40, the mark perforation 84 registers with'the mark pecker 6 which is then "allowed to rise through the perforation almost immediately to be withdrawn. Accordingly the mark pecker 6 senses the presence. of the perforation 84 and the effect is that the contacts 8! are closed while the contacts 83 are opened so thata mark condition is :applied to the line L. The mechanism for this operation is described presently. 'Prior to thesecond step of the centerhole feed (i. e. during the completion of a feeding movement by the pawl 4 I) the space perforation 88 is brcught'into register with the space pecker I which then enters the perforation and is Withdrawn. This has the effect centerhole .feed the perforation .86 registerswith' the pecker 5 andisexplored thereby so that the contacts/8| are closed and thec'ontacts' tE-opened to apply a mark condition to the'jline L. Before the second step of the centerhole "feed, during the completion of a feeding stroke by the pawl 41,.the

space pecker l rises and finds no perforation inregister therewith and the effect of this is that the mark condition is maintained, the reason for this being as described below. Prior to the first stcpof the next centerhole feed, the packet 6 rises once more and detects theabsence of any perforation-sothat the mark condition is still maintained. Before the second step of this next .centerhole edge 93 so. that line is returned tothe space feed; however, the space'pecker I1 detects the per-'- foration BID with the resultthat the line is" returned to. the space condition: Therefore, a mark condition covering one and a halfcenterhole periodsfollowed by'a space condition for one half centerhole period occurs as is required for a dash. Thetwo mark peckers 6 and 8' are pivotally mounted respectivelyon markpecker actuator'le vers=IIIO and IM (Figuresl and 4) independently pivoted" on a fixed spindle I02.and the two space peckers'l and 9 are pivoted respectively on space clockwise by springs I09 and H which tend to maintain the levers in engagement with a pin III- on the rocker 3c. Now, it will be recalled that I therocker 30 is continuously rocked by the eccentric 20 s'othat' it completes one complete oscillation in each oenterholefeed. The tendency, therefore", is'for the mark peckers B and 8 to be allowed-to rise. under the influence of the springs I-06= and I01 asthe in I08rises in the first'part of the oscillation of the rocker 30; while the pin IIxI- depresses the space peckers I and 9; In the second half: of the oscillation the peckers I and 9 tend? to "follow the pin I I I-upwards while-the pin I'08 depresses the mark peckers 6 and 8; However; as the pair of: peckers 6 and I for the first transmission of a word must never be in action simultaneously with the pair of peckers 8i and 9" for the repeattransmission, a pecker discriminatingmember H2 (see particularlyiFigure 4) pivoted at H3 toabellCrank H4 pivoted'on a fixed spindle H5; is provided to disable the pairs of peckers selectively. When the bellcrank H4 is moved to raise the discriminating member II2 into engagement with fixed stops H8 and H1, stops; II 8: and I IS on the discriminating member H2 are located respectively in front of'the tips ofidownward'extensions Iand' I2I on the mark andtspace pecker: actuator levers IM and I04'so that these are prevented from rising suificiently farto enable the peckers 8 and Sto be efiective'. The other mark and space pecker actuator levers I00 and I032 are also formed with downward extensions I22 and I23 but these are so shaped that when the discriminating stops H8 and H0 are in their uppermost positions they do not impedethe actuation of the peckers B and I. Toes I24--and I25 areformed on the lower ends of the downward extensions I22 and I23 but, when the discriminating stops H8 and IIB'are in their raised positions, these toes can pass under the discriminating stops H8 and H9.

To disable-the peckers 6 and I and render'the peckers 8 and 9 efiective, the bellcrank H4 is swung clockwise as viewed-in Figure 4 to lower the discriminating:memben- I I 2-1nto engagement with fixedstops I20 andiJIZT. The discriminatingstops I'IBran-d I I3 arethen below the extensions I20 and I2.I-', so. thatthe movement of theactuator levers HM: and I04 is no longer impeded, but are in register with the toes I24 and I25 so as to prevent the packers 6 and: 'I from rising far enough to bereffective.

It may be noted at this point that the mark pecker 8 is guided by the edge of a fixed member I28; (Figures 4 and 5) against which it is held by asprringIZS (Figure 4). The space pecker'll'fis heldby aspring I30 against-a lug I3I on a slide betweena position in which the space pecker! lies half a 'centerhole feed ahead of the mark pe'oker8, just asthepecker I' is slightly ahead of the'pecker 3; and a position in which the-peckers 8land- 9 :are' in transverse-alignment with respect tothe tapefe'edc 7 To enablerthe contacts 8| and 83m beoperated inaccordance' with the selections of the peckers', latchilevers I33 and I34 (see particu1arlyFigures 4- and: 5) are pivoted respectively on the mark pecker; actuator levers-I00 and IN, and latch levers l35 and I36 arepivoted respectivelyonthe space actuator levers I03: and I04.- Each of the i latchlevers I33; I34; I35 and I36 is 'formedat" its lower-en'd'with a notch I311 Nowsuppose that" the rocker 302 is swinging counterclockwise as viewedaimFigure-s 1i and" 5, soithat one mother'- oirthevmarkzpecker actuator levers I00tand I01;

accordingzto the setting of the pecker discriminat in member H2, is allowed to rise under the in fiuenceofzits spring? I06 or" Illlxfarenough for'the" pecker: Ii-orr 8: to reach the paper tape; if thereis noperforation in register with the pecker: the movement of the pecker'istarrested. by the paper before therassoc'iated" latch lever I33 or I34rises high. enough for its? respective notch to register with 3. lug I40'on' a lever I41: pivotedfon the spindle? I I5. Then, inthe return movement of the pecker 6- or Ii there is no efiect on the contacts III and 8 3; If, on the other hand, the pecker 6 or 8 registers with a perforation, it'rises 'far' enough for the notch I37 in the associated one of thelatch levers I33 and I34 to-be pulled into engagement with the'lug I40by a spring I42 or I43, the springs I42 and: I43 being connected respectively to the latchlevers I33 and I34. Then, when the actuator lever I00 or IOI is urged downwards by the rocker pin- I08, the latch lever I33or I34 swings the lever I4I downwards away from a stop I44 against the action of a spring I45. In this movement'thelever I4! and lug I40 depress both the left-hand endias-viewed'inl' igure 1) of alever I4Ii,pivoted' on a fixed spindle I I'I and a lug I48 on a contact actuating rocker I49 pivoted on a fixed spindle- I'50; The movement of the lever I46 takes place against the action of a spring I52 and causesa lug I5I' to raisethe left-hand ends of levers I53 and" I54 about a fixed spindle I55 against the action of" springs I55 and I51 connected'respectively to'the levers. At the end of the movement of the lever I46a' latch lever I58, under the-actioniof a spring I59, snaps into position under the lug I'5I so as to maintain this in its raised'position. The counterclockwise movement of the contact actuating rocker 148 under the action of the lever I4I causes pins- I 50 and I8I on the rocker I49; by cam action, to swing a second contact actuating rocker I62 about afixed spindle I53 in a clockwise direction so as to allowthe right-hand end of a leafleft-hand end'of the leaf-spring I84 toopen the contacts 83; Thus; the llneL'i's changed over-from the space condition to the mark condition". In

this movement, the pin I60, after riding up a cam surface to bring about the necessary movement of the second rocker I62, engages an arcuate surface 58' having its center of curvature at the spindle I50. The engagement of the pin I60 with the arcuate surface 53 serves positively to hold.

the second rocker I62 in the position to which it has been moved. A's thelatch lever- I33 or I34" is depressing the lug I40"0n' the lever I4I, a projection I" (see particularlyfFigure 'on a downward extension I66 at the left-hand side of the pecker actuating rocker30 bears on this latch lever I33 or I34 and swings it out of engagement with the lug I40, the latch lever being moved against the action of its respective spring I42 or I43. Accordingly the lever I41 is immediately returned into engagement with the stop I44 by the spring I45. There is, however, no force tending to cause the contact actuating rocker I49 to follow the lever MI in its return movement so 'thatthe line remains in the mark condition. Moreover,; the latch leverv I58 prevents the lever I 46 from following the lever MI in its return movement. Thllsthe right-hand ends of the levers I53 and I54 remain depressed against the action of the springs I56 and I51 and it is to :be particularly noted that these levers take up this position when the line is changed over from the space condition to the mark. condition. f

The action of the space packers I and 9 is similar, and when the rocker 30 is moving in a counterclockwise direction, the pin III allows the pecker 1 or 9, whichever the discriminating member I I2 permits to be in action, to rise to the tape under the action of the associated spring I09 and H0. If a perforation is explored, the associated latch lever I35 or I36 is raised far enough for its notch I31 to register with a'lug I61 (Figure 1) on a lever. I68 pivoted on the spindle I41. If no perforation is sensed, the notch I31 cannot engage the lug I61 and in the return movement of the pecker under the action of the rocker pin II I no change in the so that the latchlever I 35 highest point, the notch" to engage the lug I61 under the action of a spring I69 or I10, these springs being arranged to act respectively on the latch levers I35 and I36, In the downward movement of the latch lever I35 or I36 therefore, under the action of. the rocker pin III, the lever I68 is moved counterclockwise away from a stop .I1I against the action of a wire spring I12. "In this movement the lug I61 acts on an arm I13 on' the contact actuatingrocker I 49and swings this rocker clockwise aboutthe spindle I50. 'The rocker pins I60 and I'6I then coact with the secondcontact actuating rocker I62 to open the contacts BI and close the contacts 83. The line is then changed over from the mark or I36 is raised to its I31 thereon is caused there are single state of the apparatus occurs. Assuming, however, that there is a perforation and rotates the ratchet condition to the space condition by the closure of the contacts 83 and the opening of the contacts 8i. In this movement, the pin I 6I, after riding up a cam surface .to push the left hand end of the second rocker I 6.2-downwards, engages an arcuate surface 59 having its centerof curvature at the spindle pin I6I with the arcuate surface 59 serves positively to hold the contacts in the .position in which the line is in the spacecondition. A lug I14 on the lever, I68 acts on an arm I15 integral with the latch lever I58 so that, as the lever I68 is moved counterclockwise, the latch lever I58 is released from the lever I46 so that the right-hand end of this lever descends under the action of the spring I52 until its left-hand end once more engages the lug I40 on the lever MI. The two levers I 53 and I54 are, therefore, freed to respond to the action of line L is changed over to a space condition. A projection 91 on a downward projection 98 on the rocker 30 releases the latch lever I 35 or I36 from the lever I68 which is returned to the stop I50. The engagement of the their springs I56 and I51 when the that the right-hand ends of the I'll while the lever IE8 is made ready to engage the lug I5I again.

Before describingthev operation of the apparatus as the tape is being fed by the sprockets '3 and4, it must be mentioned that the space between two consecutive words in'a transmission is represented by three centerholes that are not associated with any code perforations, that is to say the distance between the lines X and Y in Figure 8. Actually it will-be seen that four centerhole feeds are required to cause the tape to travel a distance equal tothespace between the lines XandYj It is also to be noted that in Figure 8 real'word's are not shown; but the two special cases, which sometimes arise in practice, in one of'whichlthere are single dots (each representing: the letter E), and in the other of which dashes (each representing the letter T), are shown respectively in the upper and lower parts of Figure 8.

' Let it now be assumed that a substantial length of blank tape is being fedthroughthe apparatus prior to the arrival of code perforat'ions at the point where the packers 6 and 1 are operative. While the blank tape is passing, both the sprock ets 3 and 4 are in action and there is no loop of tape'b'etween them. The line is in the space condition, the" contacts 83 being closed. The peckers 6 and 1 arein action but in each exploring movement are arrested by thetape, no

code"perforation being sensed. The frame 33 is being rocked ,to-and-fro about the spindle 34.

In this rocking movement three .pawls A, B and C (see particularly Figure 2) are' carried to-andfro by a'spindle' I80 the frame 33. In each forward movement of the harness the pawl Aengages' a tooth on a ratchet AA; pivotally mounted on a fixed spindle 200, AA a' short distance against the action of a coil spring I8I (Figure 2) which at one end engages the ratchet AA and at the otherend engages a fixed stop "I82. The pjawl A'is maintainedv in engagement with the ratchet AA by awire spring I83 which at one end engages a tail I84 on the pawl A andrat the other end reacts against a' fixed bar I85. The forward movement of .the frame 33 causes the pawl A to move the ratchet AA in .such a way that a stop. pin I86 o'ntheratchet AA is separated from theflxed stop I82. However, owingt'o the fact that a backlock lever I 81 is held away from the ratchet AA by a lug I88, the movement of the ratchet AA reverses during the return movement of the frame 33' so that the stop pin'l86 returns to the stop IBZ. I'Ihus, as the blank tape is passing, theratchet AA is merely rocked vto-and-fro by the pawl A. Owing to'the fact that a space condition obtains, the lug I5I' on the'lever I46 is in itslowermost position so levers I 53 and I54 (Figures 1 and 2') are raised. Thus, as the I frame 33 swings forward, a toe I89 0n the tail pivotally mounted on the spindle I8 4 'of the pawl A passes underneath the right a hand end I90 of the lever I54. 0n hand, the right hand end is interposed in the path pawl B so that, as the frame 33 swings forward, the pawl B is caused to swing downwardsabout the spindle I against the action of a wire spring I 93 which acts on'the'tail I92 and reacts against the fixed-bar I85. vAccordingly, during the rock ing of the frame 33 whil 'the blank mg, no movement is impartedto a the other H I 200, by the pawl B, and a stop pin I94 (Figure 1) on the mounted at the upper end of I91 oflthe lever I53 of a tail I92 on the tape is passratchet BB,

ratchet BBremains in engagement with a fixed stop (not shownrslmilar to the fixed stop. I82,

theratchet BB being acted on bya coil spring which is similar to the coil spring l8'l (Figure 2) but is onxthe remote sid of the ratchet BB, from that appearing in Figure 2. The end of the coil spring which engages the ratchet BB appears at I 95 in Figure 2. During the passage of the blank tape, moreover, the'pawl C has no operapawl C is urged. towards the ratchet CC by a wire spring I 99 which at one end acts on the pawl C; and-at the, other end reacts against the fixed bar i851; To" enable-the pawl C to rotate the ratchet CC, '9; backlock lever pivotally mounted. on. av fixed spindle [38 has to be in position to engage the teethof. the ratchet. CC, but the backlock lever 20.! when the apparatus is in the position. being considered; is held away from the ratchet CC against the action oi a spring 2BZby one end of alever' 203 engaging a pin 281 on the backl'ock lever-1M. Accordingly, as the pawl C moves, toand-fro it merel rocks the ratchet? CC backwards and, forwards away from; and towards the point at which the stop pin l'afi' engages the fixed stop m; It is to. be noted, at this point that. the lever 203, which holds the backlock lever 20 in its. inoperative position, is pivoted upon a fixed spindle 205 (Fig- 3) and at its left-hand endcarries a spindle 2'86 upon which the sprocket. discriminating member 63 is mounted; While both the sprockets 3 audit (Ei'glllfe 1)' are. rotating, the discriminating-stops 62 and 112' are held beneath the paths oi thegl'ower" ends of the tails 64, and in. of the'pawls' 44' and 5h These discriminating stops s2 and- 1,2 are held in this position by latch lev rs-2m and 208' (Figur 3) that engage lugs 289 and 2H)? on the kzliscriminating member 63; The latch levers 201' and m are urged towards th e -'lugs 205" and H0 by wire-springs 2 H and 21.2 which react respectively against fixed rods 2113. and-Ill. There is, a further" latch lever 215 which can, engage; the lug: 2 I 0' under the action of. spring ftBgreacting against the rod 211, butv thisfllaitch lever 215 is held out of engagement. with the lug llll while the blank tape is passing, because there is then no loop' of tape. gathered between; the sprockets 3 and I so that the, center peckerslo and H? (Figure 5'), which are carried,

' byth'e limbs of a U shapedwir 211, are depressed.

against a lug 2W8 on, a bellcrank. 2 is pivoted on a-fixed spindle 220-, and; against the action of. a. spring I38. The lower end of.the bellcrank 2l9 bears against a lug 221 on the latch. lever 2.115. holdingthc latch lever in its inoperative position.

Nowsnpposing a word, which for convenience can be regarded as a word occupying several centerholes'on' the tape, arrives at the. peckers- B7 and 1. The first mark pert'orationof this word; on. being sensed by the pecker 6', resultsin the line being" changed over to the mark condition in the manner described above, and the left-hand ends of the levers [539316. I54 are allowed by the lever Mo toswins counterclockwise under the. action of the springs I56 and I51. Accordingly the end. I'Slj of the lever IE3 is lowered so that it. is no longer interposed in the, path of the tail '52" Fi ure 2). on the pawl 3.1 Thus, in. th to-and-fro. motion of the. frame. 33 the pawl. 13

is able to. feed the ratchet BB. forward against the action of its associated coil spring, return motion of the ratchet BB being prevented by a backlock lever 222v that is pivoted on the fixed spindle l5! and urged towards the ratchetBB by a spring (not shown). The. first step in the rotation oi" the. ratchet BIB. causesa cam 223 to move beyond a projection 224: on one arm. 22.5 of a U-shaped lever 226 pivoted on the spindle #55. The other arm 221 of this. U-shaped lever is. formed with the. lug I188 against which the baoklock lever I81 for. the ratchet AA bears. The. U-shaped lever 226 and the backlock lever 1-81 are urged clockwise by springs 22.8 and 229 so that,. as. soon as the cam 2Z3 releases the U-shaped lever 226,, the. backlock lever 181. is allowed to engage the ratchet AA. Nevertheless this does not mean that the ratchet AA is immediately stepped round by the pawl A, because the aforesaid movement of the lever 154, under theaction of the lever 146., causes the. end I of the lever 54. to be interposed. in the path, of the toe I89 so that, in the toeand-fro movement of the frame 33, the pawl A. is rocked about the spindle raowithout engagingthe ratchet AA.

It has already been explained that the space between two. words is occupied on the tape by three centerholes that are not associated with any perforations. It is, also to be. remarked that the. letters in any word containing more than one letter have their code perforations separated by a single centerhole associated with no code perforation. Accordingly, in the. passage, of? a word past the peckers E and 1. there will generally be centerhole periodsv during which the lever I46 is returned to, the point at which the lug [51' is. in its lowermost position. This enables the spring P5] to return the lever [51 for one, center.- hole period to a position, in which its end I90 is. raised above the toe I89 so that. the ratchet AA is fed round one toothand held in the position in which it is fed by the backlock lever I81. However, assoon as the next letter in the word arises, with the result that the. lug I5! is again raised; to move the lever l5! clockwise and interpose the end I90 in the path of the toe t89, the pawl A is swung downwards in the next forward stroke of thefra-rne 33: and, in swinging downwards, the end of the pawl A depresses the right-hand end of a lever 2-30; swinging the latter about a spindle 23% andcausing a lug 232" to act on an arm 233 integral with the backlog lever F81. The latter thus momentarily withdrawn. against the action of the spring 229 from the ratchetso that thelatter is returned by the coil spring I81 toi i'ts initial position in which thestop pin 86' engages the stop (82. A letter space, therefore, merely causes the: ratchet AA to be fed round one toothand returned to its initial position without performing any function. Q

On the other hand, a letterspace has noeffact on the ratchet. BB3 because when, as aresult of. a letter space, the lever I 46 is moved clockwise, the lever does not follow the lug lot because. when; the. lever #53: is initially moved clockwise at the; beginning of the word, it islatched; in the positiorrto. which it-is: moved by a latch. 2.34 pivoted2 on a flxedspindlei 235. andarranged. to engage a projection, 236 on the; lever L53, the latch. beingurged' to. its operative; posttion by a spring (not sbown),-.,

It will be seen. that the first perforationlin; a.

word, aiter registering with the mark pecker R has. to undergo four centerhole feeds, before aazaa r The apparatus is, therefore, contrived so that when the'first mark perforation in a word-regls-:

ters with the repeat mark pecker 8, the second sprocket 4 is arrested but the first sprocket 3 sprocket discriminating member 63 is then freeto rise under the influence of a spring 246 which tends always to swing the lever 203 clockwise and, thus, lift the spindle 206. The sprocket discriminating member rises until a projection 2'44 thereon engages a fixed stop 245 but the righthand end of the discriminating member 63 remains depressed by the latch lever 20I engaging the lug 209. It will be remembered that the latch lever 2l5 is already withdrawn from the lug2I0 and .does not impede the upward movement of the discriminating member 63 which causes the discriminating stop "I2 to be interposed in the path of the tail 10 of the pawl causing the sprocket 4 to be disabled. 'I'heupward movement of the left-hand end of the discriminating member 63 is arrested by the stop 245 before the right-hand end of the lever 203 has moved downwards sufficiently far to allow the backlock lever 20I .to engage the ratchet CC. v V I The slide 238 is supported at its right-hand end by afixed fork 250 which only appears in Figure .3, having been omitted from Figures 1, 2 and 4 so as to avoid making these figures too complicated. ;At its left-hand end the is; s upportedby a lug 25I on the latch lever 208;

The pawl B (Figure 2) may be positioned so that it tends to feed the ratchet BB forwardduring a substantial number of reciprocations of the rocking frame 33, depending on the vlength of the word being transmitted. Therefore, a gap 252 (Figures 3 and 4) is formed in the ratchet BB and is so positioned has fed theratchet BB the earn 223 has withdrawn the slide 238 against the action of the wire spring 2I2 on the latch lever208, no further feeding of the ratchet BB can take place. The slide 238, of course, remains held to the right by the cam 223 so long asthe backlock lever 222 engages the ratchet BB. I

vAs soonas a loop of tape begins to form between the sprockets 3 and 4, the center peckers wand II (Figure 5) can rise under the influence ofthe spring I39 acting through the bellcrank 2I9, which is thus swung clockwise, as viewed in Figure 5. The lug 22I on the latch lever 2I5, under the influence of the wire spring 2 I6, is, therefore, free to swing counterclockwise. The nose of the latch lever 2l5 (Figure 3) can then rest against the right-hand face of the lug 2I0 and is ready to latch over that lug when it is depressed as described below.

It will be recalled that during the passage of a word containing letter spaces these are not allowed to haveany cumulative effect -on the ratchet mark condition following a i because every letter space results inthe lever 230 (Figure 2) withdrawing the backlock' lever m1. when the wordspace arises, the end I90 of the slide 238 that when'tthe pawl B forward four teethand However,

lever I54 is allowed toremain above the toe I89 v long enough for the pawl'A to feed the ratchet AA forward byxthree teeth; further clockwise movement of the ratchet AA being prevented by a gap 253 (Figures 3.andc4) in the teeth. As the third of the three teeth i being fed forward by the pawl A a cam 254 on the ratchet acts on abutmerits 255 and 2'56respectively on a slide 251 and a slide 242, and draws'these slides to the right.

The slide 242, in this movement, causes the sprocket 3 to cease movement and the sprocket 4 to start, while the slide 251 causes the peckers 8 and 9 to become operative and the peckers .6 and 1 to cease operation; At this point it may be mentioned that when the cam 223 caused the slide 23'8to move to the right, the'lug 240 (Figure 3) on the latch lever 208 moved to the rightof an abutment 258 on the slide 242 so that a spring 24I could raise the slide slightly to bring an abutment 259 on the slide up tothe level of an abut ment 260 on the sprocket discriminating member 63 (the right-hand end of the slide 242 being mounted on a fork 2'6I, shown only in Figure 3, which permits bothlongitudinal and slightswing ing motion of the slide 242). Accordingly, when the "slide 242 is moved to the right, againsttheaction of the spring 241, by the earn 254 on the ratchet AA; two functions are performed by the slide 242. Firstly, a lug 262 on the slide releases the latch lever 201 from the lug 209 onxthe discriminatingmember 63. This permits the lever 203,'under the influence of the spring 246', to raise.

the discriminating stop 62 into the path of the tail 64 of the pawl. so that the sprocket3 is disabled. Simultaneously, however, the s1ide 242; in

moving to the right, causes the'abutment 259 to engage the abutment 2601 and swing the discriminating: member 63' counterclockwise as viewed in Figure 3, so that the lug 219 is engaged by the latch lever 2I.5, the discriminating stop 12 now beingbeneath the tail I0 of the pawl 5 l. Accordingly, the-sprocket 4 is allowed to rotate once more. As the right-hand end of the discriminating member '63 rises, a projection 263 on the discriminating member engages a fixed stop 264. As the left-hand end of the discriminating member 63 descends the projection 244 thereon engages a lateral projection =243. on the slide 242 so as to depress the latter against the action of thesprin-g MI and free the abutment 259 from the abut-- ment 260. l

When the slide 251 is moved to the right by th I cam 254; a latch lever 265, pivoted on the fixed spindle I38 and acting'under'the influence of a spring 266,- engage an abutment 267 on theslide' 251 and holds the slide in it right-hand position against the action of a spring 210 As the slide moves to the right, a lug 268 thereon acts on a wire springa2'69 so as to bias the bellcrank I I 4 in aclockwise directionas viewed in Figure 4. Thus,

the pecker discriminating member II2 tends to descend and, as the toe I25'is withdrawn from beneath the stop IIB, the right-hand end of the discriminating member H2 descends to the fixed stop I26. Then, as the toe I24 is withdrawn from beneath the stop M9, the left-hand end of the discriminating member I-I2 descends to the fixed stop I21. Thus, the discriminating stop us and I I9 take up the positions in which they disable the and I but permit the peckers 8 and 9 peckers 6 to operate. v

When-the repeat transmission begins, a mark condition again arises with the result that the end I of the lever I54 is interposed'in the path of the toe I89 of the pawl A. Thi causesthe'lever the backlock lever i8! is withdrawn from the ratchet AA which then returns to its initial position and permits the spring 2. to return the slide 242 to. its left-hand. position. However, the lefthand end of the discriminating member 63 re -l main latched by the latch lever-215 and the right-hand end of the discriminating member re mains in its upper position. On the other hand, the slide 251 remains held to the right by the latch lever 285.

It is to be noted at this .point that when the discriminating member 63 is in the position just described, the righte'hand end of the lever 283', on which the discriminating member 83 is pivoted, continues to hold the backlock lever 224 out of engagement with the ratchet CC. This is due to the fact that the back-lock lever 201 i only allowed to engage the teeth of the ratchet (36 when the discriminating member 63 isxin its highest position in which the stops 62 and 12 are pre v venting the operation of both sprockets 3 and 4.

The sprocket 4 and peckers 8 and 9 continue to operate for the repeat transmission of the word until the tape becomes taut between the two sprockets 3 and 4.. The three centerholes com prised within the word space arethen centrally located between the sprockets. The tautening of the tape has an immediate effect in that it depresses the center peckers l and H so as to swing the bellcrank 2!!! (Figure in a counter.- clockwise direction about the spindle 220. One efiect of this movement is that the lug 22! on the latch lever 215 is pushed to the right by the depending portion of the bellcr-ank 218 so that the latch lever 215 (Figure 3) is withdrawn from the. lug 210 on the discriminating member $3. Owing to the fact that the latch lever 288 is still being held away from the lug 210 by the slide 238, the spring 246, acting through the lever 203, raises the projection 244 on the discriminating member 63 into engagement with the fixed stop 245, Ac-i cordingly, the discriminating stop 12 is interposed in the path of thetail of the pawl 5| so that the ratchet 4 is stopped. Now the spindle 206 on the discriminating member 63 has been raised to its highest position by the spring 246 acting on the lever 283 and the right-hand end of the lever 203, therefore, is low enough to permit the backlock lever 28! (Figure 2) to engage the ratchet C(l which is now fed forward in a clockwise direction. However, before describing the effect of this movement of the ratchet CC, some further effects ofv the depression of the centerpeckers It and I1 and the consequent move.- ment of the bellcrank 219 will be described. This movement of the bellcrsnk 219 rcsultsin'the lug 2 H5 at the upper end thereof depressing the slide 32 aboutthe spindle 229 against the action of a spring 212 so that a lug 213 at the left hand end r 232 to be'moved in a clockwise direction so that It the pecker 9 was: not so withdrawn, it would be beyond the last space perforation in the word throughout the interval in which the sprocket 4 remains stationary and at the end of which the packers 6 and 1 are once more brought into action instead of the 'peckcrs 8 and 9, this being an interval lasting for three cycles (that is three centerhole periods or three revolutions of the shaft l8), as will be explained below. If the word ends with a dot, it will be seen that during this three-cycle interval the pecker 8 would sense the mark perforation in the dot again (after the sensing of the space perforation) owing to the l stationary condition of the tape, were it not for of the slide l32 is disengaged'from a fixed latch 214 with the result that the Slide I32 is drawn a slight distance to the ri ht by the spring 212. Accordingly, the lug I5! is moved to the position which enables the spring 138 (Figure 4) to draw the pecker 9 into transversealignment, as afore-- said, with thepecker 8, both peckers now resting against the fixed member I28. The reason for this is that the sprocket 4 is brought "to rest when the last space perforation in a word, such as the perforation 88 or 9!) (Figure 8), is in register with a line corresponding to the line X in Figure 3 and containing the pecker 8. Therefore; the last space perforation would not be sensed by the pecker 9 if itiwas not withdrawn tothefixed member I28.

the fact that a device is provided for preventing this redundant actuation of the mark pecker 8-. This device comprises a latch lever 218 ('Figure 4) which follows thelug 213 to the right as the slide I32 is pulled to the right by the spring 212, the latch lever 218 moving under the influence of a wire spring 21?! about the spindle H5. It will be seen that one end of the wire spring 211 engages the latch lever 216 and the other end engages a, lug 218 on theslide 251'. The slide 251 is drawn to the right and held in its right-hand position by the latch lever 2-65 at the instant being at present considered, so that as soon as the slide I 1 is drawn to the rig-ht by the spring 212, thelatch lever 216 is free to enable a projection 219 thereon to engage over a lug 288 on the mark pecker actuator lever ill! to prevent the mark pecker 8 from sensing a perforation. Therefore, if the last code unit in the word is a dot, there is no danger of the line being changed backto the mark condition before the first mark perforation in the next word is explored for the first transmission of that word. It may be mentioned that when the. lever 2-16 swings clockwise as viewed in Figure 4, the pecker actuator lever Illl is too high to enable the projection 219 to move over the lug 289, but during the following cycle, as the actuator lever m is depressed by the pin I88, the spring 211 moves the projection 219 over the lug 280 to latch the actuator lever.

Returning now to the ratchet CC, this, as mentioned above, becomes effective when the backlock lever 2M (Figure 2) engages the ratchet CC and the ratchet CC is then fed round four teeth by the pawl 0 after which, in all ordinary circumstances, the backlock lever 20! will be raised (in the manner described presently) once more to release the ratchet which then returns to its initial position with the-pin I96 engaging the stop I91. However, for the purposes of safety a gap 28! (Figures 3 and 4) is provided in the ratchet teeth so that the pawl C cannot feed the ratchet round more than four teeth. The first tooth feed of the ratchet CC brings a cam 282 into engagement with a lever 283. In the second and third feeding movements of the ratchet CO the cam 282 forces,

and then holds the lever 283 in a counterclockwise direction, as viewed in Figure 2, about the spindle I55 and against the action of a spring 284, In this movement the lever 283, acting on a, lug 285 on one arm, of a -U-shaped member 286, forces this U -shaped member counterclockwise about the spindle against the action of a spring 281. The result of this is that a lug 288 on the other arm of the U-shaped member 286 withdraws the backlock lever 222 from the ratchet BB and the projection 224 of the arm 225 of the U-shaped member 228 from the cam 223 so that the ratchet BB is released and returned to its initial position. The'other arm 221 of the U-shaped member 226 is also, of course, moved so that the lugl88'rc- I A lug I16, also on the U-shaped'member 286,-

acts on the latch lever 234 and releases it from the projection236 on the lever I53 which, under the influence of the spring I56, immediately returns to the position in which it engages the lug II, the latter now being in the position corre sponding to the space condition of the line. The lever I54 has, of course, already followed the lug I 5| to its lowermost position. When the first mark perforation in the next word is sensed, the levers I53 and I54 are, of course, returned in a clockwise direction and it may be noted that, in

order to prevent the end I90 of the lever I 54 from rising prematurely, a locking lever 289 is pivoted on the spindle I80 on the frame 33. This looking lever has an arm 290 which is urged towards the fixed bar I85 by a wire spring 29I. Thus, as the frame 33 swings forward in a counterclockwise direction, a lug 292 on the locking lever 288 rides over the end vents the end I 90 from rising prematurely. When the frame 33 is at the end of its backward stroke, the lug 292 is clear of the end I90 so that the latter can rise, Then, when the frame 33 swings forward, the lug 292engages the rear face of the I90 cf the lever I54 and pre- I to feed once more after an interval corresponding .to'the word space that mustfbe interposed bea' Word and the tween the repeat transmission of first transmission'of the next. i

The aforesaid counterclockwise movement of the lever 203,. through'the pin'204, causes the backlock lever I to be raised against the spring 202 so that the ratchet-CC is enabled to return;

to the initial position (in which the stop pin- I96: engages the-stop I91) after the fourth feeding movement of the ratchet CC. During this fourth feeding movement the cam 282 on the ratchet CC- is raised above the-top of the lever 283, and,'in the return movementof the ratchet CC underv the action of its associated coil spring'corresponding'.

to the coil spring I8I of theratchet AA, the cami 282 bears on the top of thelever 283.arid desend I90 and the locking lever 289 swings ineffectively about the spindle I80 against the action of the wire spring 29 I. I

The backlock levers I81 and 222 are withdrawn during two complete cycles so that adequate time is given for the ratchets AA and BB toreturn to their initial positions. As the ratchet BB returns, the cam 223 thereon is restored to the position shown in Figure 2, the projection 224 on the arm 225 being held, at this moment, out of the path of the cam 223 by the engagement of the lug 288 with the arm 225. This movement pf the cam 223 allows the wire spring 2I2 to draw the latch lever 208 (Figure 3) slightly to the left so that the nose of the latch lever 208 rests against the lug 2I0' on the sprocket discriminating member 63. Thus, the latch lever 208 is ready to latch over the lug 2I0 as'soonas the discriminating member 63 is depressed. The latch lever 201, is also ready to latch over the lug 209. on the discriminating member 63. The said depression of the discriminating member 63 takes place when a cam 293 on the ratchet CC engages a cam sur-.

face 294 on the lever 203 and lifts the latterso as to swing it counterclockwise about the spindle 205 and depress the spindle 206 (FigureB). I As the spinle 206 descends, the right-hand end of the sprocket discriminating member 03 descends until the projection 263 thereon engages a fixed stop 99. As the discriminating member ap proaches this position the wire spring 2 urges the latch lever 201 into latching cooperation with the lug 209. Thenthe fixed'stop 99 acts as a fulcrum for the discriminating member 63 while, as the spindle 206 continues to descend, the lefthand end of the discriminating member is lowered, the left-hand projection 244 thereon pressing on the lateral projection 243 on the slide 242 and lowering the left-hand end thereof against the action of the spring 24 I This continues until the wire spring 2H3 moves the latch lever 208 into latching cooperation with the lug 2I0 on the discriminating member 63. The latter is now-in its lowermost position and the discriminating stops 62 and 12 are both beneath the tails 64 and 10 of the pawls 4I and SI so that both ratchets start presses it against the-action of the spring-284, the. lever 283 being furnished at its'lower end with a slot 300 which, besides permitting the pivotal;

movement of the lever 283 about the spindle I55,

also permits this downward movement of the lever. It Will-:be seenthat this downward move-.- ment of the lever permits the cam 282 to snap past the lever 283 which, except when it isfl'moved counterclockwise by thecam 282, bears against a fixed stop 30I The U-shaped member 288then also bears against a fixed stop 302. Returning to'the' final feeding movement of the ratchet CC, this results in a lug 303 (Figures '2 and 4) at the end of the lever 203 lifting an arm 304 integral with the latch lever 285, so that the latter is raised against its spring 266 from the abutment 261 on the slide 251 so that the latter is withdrawn by the spring 210 (Figure 4) to-its left-hand position. An incident to this movement is'thattheflug 218 "on the slide 251-withdraws the latch lever 216 from the lug 280 on the mark pecker actuator lever IOI Also, as the spring 210 urges the slide 251 to the left, itswings the bellcrank II 4 clockwise soas to lift the pecker discriminating member II2'to' position the discriminating stops II8 and II 9 at the-points in which they disable the" repeat peckers 8' and '9 but render'the peckers 6 and 1 operative;

From the foregoing description it will be seen that after a period in which both the sprockets 3 and 4 are idle and the'line is maintained in the space condition (the duration of the period cor: responding to the word space that must be interposed between the repeat transmission and the first transmissionof the next word) the, movement of the lever 203 starts both sprockets 3 and 4 simultaneously and renders the peckers 8 and 1 operative. Accordingly, the first mark perforag tion in the next word is, immediately explored with the result that the line is changed over to the mark condition and the feeding movement of the ratchet BB is initiated once more, as already described, so as to disable the sprocket 4 at the appropriate moment to cause the tape to gather between the-two sprockets 3 and 4. The sequence of operations then, as already described. e v

It will be noted, however, that although the transmission of the next Word has already begun the slide I32 hasnot yet'been returned to :its initial position. The movement to the left, as

aforesaid, of the slide251 prior to the-transmise s'ion of then'ext' word has already carried a lug 306 (Figure 4) from a projection 301 on a detent of course, proceeds between the first and second transmissions of the next word, the bellcrank 2 I9.moves so as to allow a spring 3 I 0 to swing the detent 308 counterciock-' wise to bring a shoulder 3I I thereon into the path of an arm 3I2 ona bellcrank 3I3 carried by the pin Ill on the rocker'30. Thus, as the rocker 30 swings clockwise, the bellcrank 3I3 is swung coimterclockwise by the shoulder 3H away from a fixed stop 118 (Figure 5) upon which the bellcrank 313 normally slides, and against the action of a spring I'll. The top of the bellcrank 3I3 is thus caused to act on an abutment 3 on the slide I32 and return this slide to the latched position. When the slide 251 (Figure 4) is pulled once more to the right to initiate the repeat transmission of the said next word, the lug 308 acts on the projection 301 to shift the detent 308 clockwise against the spring 3.!0. Therefore, the bellcrank 3 I 3 is able once more to follow the path in which it bears continuously upon the stop 118 and, at the end of the repeat transmission, the slide I32 can be unlatched and remain in its unlatched position.

If it is required to prevent 'the apparatus from operating as aforesaid and to transmit each word once, a spindle 315 (Figure 1) is turned to cause a cam 316 to permit a spring 311 to cause a hook 313 on a bellcrank 3i 9, pivoted on .a' fixed spindle 320, to engage over a lug SM 0;; the tail I92 of the pawl B so that this is always swung away from the ratchet BB as the frame 33 swings counterclockwise Thus, the ratchet BB is never operated in these circumstances to pull the slide 238 to the right and release the backlock lever I81.

When repeat transmitting is taking place, in the special case where the letter E is separated from the next succeedingword by a word space (as shown at the top of Figure 8) the first transmission is accompanied, as usual, by the actuationof the ratchet BB. Thus when the isolated dot, representing the letter E, reaches the repeat sprocket 4, the slide 238 'is drawn to the right to stop that sprocket. .I-Iowever, owing to the absence of any further mark perforation beyond the dot, the ratchet AArotates so as to draw the slide 242 to the right simultaneously with the slide 238. Accordingly, the lug .240 (Figure 3) on the latch lever 208 does not :move beyond the abutment 258 and the spring 24] cannot lift the slide 242 to bring the abutment 259 into engagement with the abutment 200. The movement or the slide 242, therefore, does .notper-form its usual function of starting the sprocket but it does, as usual, act on the latch lever 201 to stop the sprocket 3. In this case of the letter E appearing as a word, also, no loop of tape arises between the sprockets 3 and l, and

so the center peckers 10 and l I are not allowed to rise. Therefore, the abutment 3 is not interposed in the path of the bellcrank 3I3 and the mechanism for detecting the physical characteristics of the record strip representing the division between words, mechanism responsive to said de-. tecting mechanism for repeating the transmission of each word before the transmission of the next 1. word.

2. Telegraph transmitting apparatus comprising, in combination, means for feeding therethrough a record strip bearing a series of words represented in a code comprising permutations oi elements such as dots and dashes, and, further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for controlling said feeding means to cause each section of the record strip that contains the record of a word to undergo two separate and distinct feeding movements, means for exploring, during each of said two I movements, the code elements representing the particular word, and means controlled by said exploring means for transmitting signals corresponding to the code elements twice for each word.

3. Telegraph transmitting apparatus compris ing, in combination, means at one point in the apparatus for the feeding therethrough a record strip bearing a series of words represented in a' code comprising permutations of elements such as dots and dashes and; further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, second means at a second point in the apparatu for feeding the record strip therethrough, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for operating said two feeding mean alternately, means for exploring the code representa- 0 tions of one particular word in each of two sucslide I32 isnot relatchedbut remains in the uncessive feeding movements of the record strip efiected respectively by said two feeding means, and means .for transmitting signals, corresponding to the code elements in the said word, firstly during the first of said feeding movements and secondly during the second of said feeding movements.

4i. Telegraph transmitting apparatus comprising, in comb nation, a sprocket wheel at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, as well as bearing a line of sprocket holes to be engaged by said sprocket wheel for feeding the strip, a second sprocket wheel at a second point in the apparatus for feeding the record strip therethrough, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for operating said two sprocket wheels alternately, the strip being caused to gather between the two sprocket wheels when the first of said wheels is operating and to be fed from between thetwo wheels when the econd is operating, means for exploring the code representations of one particular word in each of two successive feeding movements of the record strip effected respectively by said two sprocket wheels, and means for transmitting signals, corresponding to the code elements in the said word, firstly during the first of said feeding movements and secondly during the second of said feeding movements. a

' representing the division between words, mechanism responsive to said detecting mechanism for causing said two sets of peckersin succession to i explore the code perforations pertaining to each word, and transmitting means controlled by said peckers for transmitting each word first in accordance with one set of peckers and then a repetition in accordance with the other set of peckers.

6. Telegraph transmitting apparatus comprisl ing, in combination, means for feeding therethrough a record strip bearing longitudinally a series of equally spaced centreholes and a series of words represented by code perforations each associated with one centrehole, the strip further bearing physical characteristics indicating the division between-the words in each pair of consecutive words, second means at a second point in the apparatus for feeding the record strip therethrough, each of said two feeding means being adapted to feed the record strip forward in steps determined by the spaces intervening between each pair of centreholes, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for operating said two feeding means successively in respect of and for a period.correspondin'g to the length of each word, means for exploring the code perforations representing a word in each of the two successive feeding movements pertaining to the word, and means for transmitting signals corresponding to the code perforations representing the said word firstly during the first of the said feeding movements and secondly during the I second of the said feeding movemen '7. Telegraph transmitting apparatus comprising, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented by perforations arranged according to the Morse code and, further, bearing physical characteristics indicating the division between the words and each pair of words, and second means at a second point in the apparatus for feeding the rec rd strip therethrough, two ratchet and pawl mechanisms allocated respectively to said two feeding means for actuating same, mechanism for detecting the physical characteristics of the record strip representing the division between words,

means responsive to said detecting mechanism for disabling said two ratchet and pawl mechanisms in succession whereby each portion of the strip bearing a perforated representation of a word' undergoes two separate feeding movements, means for exploring the perforations representing the word in each of said feedingmovements, and means for transmitting signals corresponding to the said perforations firstly during the first of said feeding movements and secondly during the second of the said feeding movements.

8. Telegraph transmitting apparatus compris-- ing, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented by perforations constituting permutations of signal elements of two different kinds, the strip further bearing characteristics indicating the division between the words in each pair of consecutive words, second means at a second point in the apparatus for feeding a record strip therethrough, two ratchetand pawl mechanisms, each comprising two staggered ratchet wheels and two pawls, allocated respectively to said two feeding means for driving I same, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for causing said two feeding means to operate in succession by first prethe perforations representing a word undergoes two successive feeding movements firstly under.

the control of one ratchet and pawl mechanism and then under the control of the other ratchet and pawl mechanism, means for exploring the code perforations representing the said word in each of the said feeding movements of the record strip, means for transmitting signals according to the perforations firstly during the first of the said feeding movements and secondly during the second of the said feeding movements.

9. Telegraph transmitting apparatus comprising, in combination, means for feeding there'- through a record strip bearing a series of words perforated according to a code consisting of permutations of two kinds of elements and, further, bearing characteristics indicating the division between the words in each pair of consecutive words, such characteristicsconsisting of a gap of predetermined length between the last code perforation in one word and-the first code perforation in the next word, two sets of peckers for exploring the code perforations, mechanism for detecting a gap as aforesaid between the groups of perforations representing consecutive words, mechanism responsive to said detecting mechanism for causing said two sets of peckers in succession to explore the code perforations pertaining to each word.

10. Telegraph transmitting apparatus comprising, in combination; means at one point in the apparatus for feeding therethrough a record strip bearing a serie of words representedin a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the two words in each pair of consecutive words, second means at a second point in the apparatus for i feeding the record strip therethrough, means responsive to the code elements for transmitting signals corresponding to same, a cyclically mpvable member, means operable upon the transmis- SiOn oft-he first code element in a word for initiating the movements of said cyclically moving member for a predetermined number of cycles,

ing, in combination, means at one point in the I bearing a series of words represented in a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the two words in each pair of consecutive words, second means at a second point in the apparatus for feeding the record strip therethrough, means for sensing the code elements at each of said points, means for transmitting signals in accordance with said sensing means, a cyclically movable pawl, a ratchet operable by said pawl, means operable upon the transmission of the 'first code element in a word for initiating the movements of said pawl for a predetermined number of cycles, means controlled by said ratchet for arresting the strip at said second point upon the completion of said predetermined number of cycles, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for initiating the feeding of the strip at said first point and arresting the feeding of the strip at said second point. 12. Telegraph transmitting apparatus comprising, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising permutation of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the two words in each pair of consecutive words, means for sensing the code elements at the first of said points, second means for sensing the code elements at the second of said points, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for transmitting signals corresponding to the code elements in a word firstly under the control of said first-mentioned sensing means and, as a repetition prior to the transmission of the next word, under the control of said second sensing means, a cyclically movable member, means operable upon the transmission of the first code element in a word, in the first transmission of the word, for initiating the movements of said cyclically movable member for a predetermined number of cycles, means for arresting the strip at said second point upon the completion of said predetermined number of cycles, a second cyclically moving member controlled by said detecting mechanism for arresting the feeding of the strip at the first point and initiating the feeding of the strip at the second point, whereby that portion of the strip bearing the representation of a word of any length, after being fed past said first point, is fed past said second point.

13. Telegraph transmitting apparatus comprising, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the two words in each pair of consecutive words, means for sensing the code elements at the first of said points, second means for sensing the code elements at the second of said points, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for transmitting signals corresponding to the code elements in aword firstly under the control of said first-mentioned sensing means and,

apparatus for feeding therethrough a record strip as a repetition prior to the transmission o t next word, under the control of said second sens ing means,'a cyclically movable member, means operable upon the transmission of the first, code element in a word, in the first transmission oi the word, for initiating the movements of said cyclically movable member for a predetermined number of cycles, means for arresting the strip at said second point upon the completion of said predetermined number of cycles, a cyclically move able pawl, a ratchet operable by said pawl, means associated with said detecting mechanism for in itiating the movement of said pawl for a preder termined number of cycles, said ratchet being operative on the completion of said predeterm ned numberof cycles to arrest the feeding of the strip at the first point and initiate the feeding of the strip at the second point, whereby that portion of the strip bearing the representation of a Word of any length, after being fed past said first p int, is fed past said second point.

14. Telegraph transmitting apparatus comp i ing, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes, and, further, bearing physical char-.- acteristics indicating the division between the two words in each pair of consecutive words, means for sensing the code elements at the first of said points, second means for sensing the code elements atthe second of said points, mechanism for detecting the physical characteristics cf the record strip representing the division between words, means responsive to said detecting mech anism for transmitting signals correspondingto the code elements in a word firstly under the con trol of said first-mentioned sensing means and, as a repetition prior to the transmission of the next word, under the control of said second sensiing means, a cyclically movable member,-means operable upon the transmission of the first code element in a word, in the first transmission of -the word, for initiating the movements of said cyclically movable member for a predetermined number of cycles, means for arresting the strip at said second point upon the completion of said predetermined number of cycles, a second .cycli cally movable member, means associated with said detecting mechanism for initiating the move ment of said second cyclically movable member for a predetermined number of cycles correspond.- ing to the period required to feed a point on said strip from said first point to said second point, whereby that portion of the strip bearing the representation of a word of any length, after being fed past said first point, is fed past said second point.

l5. Telegraph transmitting apparatus comprise ing, in combination, means for feeding there, through arecord strip bearing a series of words perforated according to a code consisting of per mutations of two kinds of elements and, further,

bearing characteristics indicating the division between the words in each pair of consecutive words, such characteristics consisting of a gap at predetermined length between the last code per foration of one word and the first code perform tion of the next word, two sets of peckers not exploring the code perforations, mechanism, in? cluding an element arranged to remain in a prev determined position for a period corresponding to the time taken by said-feeding means to feeds point on the strip past a point in he apparatus for detecting a gap as aforesaid between the in succession to explore the code perforations pertaining to each word.

16. Telegraph transmitting apparatus compris ing, in combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising, permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, second means at a second point in the apparatus for feeding the record strip therethrough, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for causing said first-mentioned feeding means to operate while said second feeding means remains idle and the strip gathers between said two points, means for sensing the code elements representing a word while the strip is being fed by said first-mentioned feeding means, means for thereupon causing said second feeding means to feed the strip forwards while the strip between said two points becomes taut, means forsensing the said code elements representing the word while the strip is being fed by the second feeding means, means for transmitting signals corresponding to the code elements under the. control of said two sensing means, so that the word is transmitted and then retransmitted, and mechanism responsive to said tautening of the strip for resetting the apparatus for the transmission of a new word after the repeat transmission of the preceding word. r

17. Telegraph transmitting apparatus comprising, in combination, means at one point in the apparatus for feeding therethrough a recordstrip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, second means at a second point in the apparatus for feeding the record strip therethrough, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for causing said first-mentioned feeding means to operate while said secondfeeding means remains idle and the strip gathers between said two points, means for sensing the code elements representing a word while the strip is being fed by said first mentioned feeding means, means for thereupon. causing said second feeding means to feed the strip forwards while the strip between said two points becomes taut, means for sensing the said code elements representing the word while the strip is being fed by the second feeding means, means for transmitting signals corresponding to the code elements under the control of said twosensing means so that the word is transmitted and then retransmitted, a resilient device arranged to be depressed by said stripas it becomes taut between said two points, and trip members operable by said resilient device to reset the apparatus to transmit a new word after the repeat transmission of the preceding word.

18. Telegraph transmitting apparatus comprising, in 'combination,- means at one point in the apparatus for feeding therethrough a record strip bearing a series ofwords represented in a code comprising permutations of elements such as 'dots' and dashes and, further, bearing physicai' characteristics indicating they division between the words ineach pair of consecutive words, second means at a second point in the apparatus for feeding the record strip therethrough, mechanism for detecting the physical characteristics of the record strip representing the division between words, means responsive to said detecting mechanism for causing said first-mentioned feeding means to operate while said second feeding means remains idle and the strip gathers between said two points, means for sensing the code elements representing a word while the strip is being fed by saidfirst-mentioned feeding means, means for thereupon causing said second feeding means tofeed the strip forwards while the strip between said two points becomes taut, means for sensing the saidicode elements representing theword while the strip is being fed by the second feeding means, means for transmitting signals corresponding to the code elements under the control of said two sensing means so that the word is transmitted and then retransmitted,; a resilient device arranged to be de-. pressed by said strip as it becomes taut between said two points, and trip members operabl by saidresilient device to arrest the feeding of said strip at both points.

I 1 9. Telegraph transmitting apparatus comprising, vin combination, means at one point in the apparatus for feeding therethrough a record strip bearing a series of words represented in a code comprising permutations of elements such as dots and dashes and, further, bearing physical characteristics indicating the division between the words in each pair of consecutive words, second meansat a second point in the apparatus for feeding the record strip therethrough, mechanism fordetecting, the physical characteristics of the record striprepresenting the division between words, means responsive to said detecting mechanism for causing said first-mentioned feeding means to operate while said second feeding means remains idle, and the strip gathers between said two points, means for sensing the code elements representing a, word whilethe strip is beingfed by said first-mentioned feeding means, means for thereupon causing said second feed.- ing means to feed, the strip forwards while the strip between said two points becomes taut, means for sensing the said code elements representing the wordwhile the strip is being fed by the second feeding'means, means for transmitting signals corresponding to the the control of said two sensing means so that the word is transmitted and then retransmitted, a resilient device arranged .to..be depressed .by said strip asit becomes :taut between said two points, trip members. operable by the depression of said resilient'device, ratchet .and pawl mechanism rendered operative by said trip members, and cam-mechanism adapted to be. operated by said ratchet and pawl-mechanism to reset the apparatus to transmit a new Word after the repeat transmission of ,th preceding word.

. '20. Telegraph transmitting apparatus comprising, in combination, means for feeding therethrough a record strip bearing a series of words perforated according to a code consisting of permutations of two kinds of elements and, further, bearing characteristics indicating the dicode elements under 

